Capacitors are widely applied to numerous electronic terminal devices, such as a touch control sensor for touch control on a display screen of the terminal device. In a process of using a capacitor, it is indispensable to measure and analyze a capacitance value thereof. Nowadays, self-capacitance detection has become a very important measurement and analysis method.
However, since a self-capacitance tends to be relatively great, an existing self-capacitance detection method has lower sensitivity when the self-capacitance is greater; and a volume of a cancel capacitor for improving the sensitivity is larger, so that the cancel capacitor cannot be integrated, and is also excessively high in cost; and further, an increase in self-capacitance causes the sensitivity of the existing self-capacitance detection method to be lower, such that the capacitance value cannot be correctly detected. Therefore, how to improve the sensitivity of self-capacitance detection and accurately detect the capacitance value within a controllable cost range is an urgent problem to be solved.